System of regulation



F. C. HANKER.

SYSTEM OF REGULATION.

APPLICATION FILED MAY 4. 1916.

1,306,894. Patented June 17, 1919.

L za v WITNESSES: INVENTOR M Z fieaar/t 6 Hawker ATTORNEY operation of overloads so long as .condenser for the purpose to cause a furt rnnnnnrc'c. BANKER, or wI'LmNsnUne, PENNSYLVANIA, AssroNon r0 wnsrmGHOUSE ELECTRIC AND MANUFACTURING COMPANY, A CORPORATION or rnNNsnv NrA.

SYSTEM 01 REGULATION.

To all whom it may concern:

Be it known that I, FREDERIO G. HANKER, a citizen ofthe United States, and a resident of Wilkinsburg, in the county of Allegheny and State ofPennsylvania, have invented a new and useful Improvement in Systems of Regulation, of which the followin is a specification. I

' y invention relates: to' those electrical systems in which regulators are employed for controlling the field strengths of dynamo-electric machines, and it has for its object to provide means for controlling the operation of a regulator in accordance with the temperature. of thedynamo-electric machine] v It is frequently desirable to so control the a regulator for a dynamo-electrio machine, and particularly when it is-employed in. connection with asynchronous of regulatingthe voltage at the receiving end of a distributing c1rcuit,that-the ,machine'may not be in definitely overloaded and damaged by excessive heat,while, at' the same time, it should be permitted to assume temporary it is not thereby exces sively heated. According to the'prese'nt invention, the reglulator is rendered ine'fiective er increase in tation of the dynamo-electric machine when the temperature of the machine exceeds a predetermined value,-or rather to regulate to maintains, lower voltage corresponding in value to the temperature of the machine.

In the single figure of the accompanying drawing which diagrammatically illustrates an electricalsystem embodying my invention, a dynamo-electric machine 1, that may be a synchronous condenser or a generator, has its armature 2 connected to a distributing circuit 3--4-5, its fieldmagnet winding 6 beingsupplied with exciting current from.

an exc1ter having an armature 7 and .a' fieldmagnet winding 8. In series with the exciter field-magnet w nding Bis aresistor 9 the effective value of which 'is controlled by a relay 10 that is adaptedto open'and close a thereto. The relay 10 is circuit in shunt 7 provided with an actuating winding 11 that receives current from. the exciter or from any other suitable source, and a circuit in shunt thereto is controlled by stationary and movable contact members 12 and 13 that the field exciarm t at carries relay vtionary .fulcrum Specification of Letters Patent. Patented J 119 17, 1919, Application filed Kay 4, 1918. SeriaI'No. 95,321.

constitute parts of the main control element of a regulator. Z v

-Thesaid main control element comprises further a bell-crank lever'14 that has a staat 15 and supports and-provides a fulcrum at 16 for a second lever 17 havin an upwardly and laterally-extending the contact terminal 13.

The lever14 is actuated by an electromag- 19'that receives current. from the distri uting circuit 34.-5 through a transformer 20 and a resistor 21. The efiective'value of the resistor 21 is controlled by a relay 23 having an actu-. atingwinding 24 that is connected in par- ,allellwith-the relay winding 11, and is also controlled by the; contact terminals 12 and The engagement and disengagementof the contact terminals 12 and 13 causes the 23 to open and close a shunt to a portion of the resistor 21, thereby causing alternate'increases and decreases in the degree ofenergization of the Winding 19 which, accordingly, vibrates the lever 14 and with it the contactterminal 13. The lever 17 is actuated by an electromagnet having an energizing winding 25 that receives current proportional in value to the voltage of the circuit 3--4--5 through the transformer 20 and a resistor 26. I v V The effective values of the resistors 21 and 26 are controlled by two relays 27 and 28, respectively, having actuatin windings the circuits of which are control ed by a galvanometer or relay 29 that is connected between two corners of a Wheatstone bridge 30, the resistor 31, constituting one side or leg thereof, being embedded in the structure of the dynamo-electric machine 1, or being otherwise located in proximity to the art or parts of the machine that aremost-li ely to become overheated when an excessive load I is applied.

In the operation of the system, the voltage regulator serves, as isusual with re gulators of this type, to so vary, the field strengths of the exciter and the dynamo-electric machine as to maintain thevoltage upon the circuit 3-4--5 substantially uniform. For instance, if the voltage of-the circuit 3-4-5 decreases because of an increase in the load,

the contact terminal 13 is theretoward, or into engagement with,

the terminal 12. Upon engagement of the contact terminals,'the relay windings 11 and 2 are short-circuited and, consequently, the

resistor 9 and a part of the-resistor 21 are likewise short-circuited. The field strengths of the exciter and of the generator or syn chronous condenser are thereby increased to eflect an increase inthe voltage of the dynamo-e'lectric machine and of the distributing circuit. The winding 19 also becomes more strongly energized, and, accordingly,

moves the contact terminal 13 away .fromthe terminal 12. The operation of'the regulator is, of course, opposite to that just' de-,

scribed when there is a tendency for-the voltage 345 to increase above itsnormal.

mo-electric machine l'as to enable it tocarrythe load or to assist in carrying it. In the case of a synchronous condenser, this is, of course, the wattless part of the load, However, if the excessive load persists for such a period as to cause excessiveheating of the I dynamo-electric machine, an unbalanced condition is established in the Wheatstone bridge as a result of which the relay. 29 operates to close the circuits ofithe relays 27 and 28 which thereupon short circuit portions of the resistors '21" and -26.","lhe result is that the windings l9 and 25 of the regulator-1 become more strongly energized and operate to cause a decrease in the field strengths of the exciter and of the dynamo-electric machine and, consequently, the dynamo-electric machine is prevented from assuming as large a-proportionnf the load as was previously carried by it, and 'the machine isthereby preventedfrom being damaged by excessive heating.

ltiwlll, of'eour'se, be understood that other: specific means than that illustrated ma be employed for governing the Operation of the o theregulator to preventv excessive hea'ti dynamo-electric machine, and also that'other formsof regulators may be employed, if-desired, Without-departing from the spirit and scope ofthe inventiomas set forth in the ap pended claims.

' 1 claim as my invention:

1. The combination with a dynamo-else trie machine, and means for regulating its therewith I a a 8 field strength comprislng an actuating w1nding and a resistor in series therewith, of means formodifying the efi'ective'ness of the resistor when the temperature of the dynamo-el'ectric machine exceeds a predetermined value by reasonof an abnormal current flow through the machine fora protracted period.

' 2. The'combinationwith a dynamo-electric machine, a'Wheatst-one bridge comprising a resistor locatedin the dynamo-electric machine, and a relay connected between two of the corners of the Wheatstone bridge, of

. means for-regulating the field strength of the dynamo-electric machineand afi'e'cted itsoperati'on by the said relay. a

13. The, combinat on with a dynamo-electric machine, a Wheatstone bridge comprising a resistor located in the dynamo-electric machine, and a'relay connected between two of the corners of the Wheatstone bridge,

Of' means for regulating the field strength of the dynamo-electric machine "comprising an actuating winding and a resistor in series the said relay controlling the degreeofefl ectiveness of said resist0r.- 4. Thecgmbination with a dynamo-electric machine provided with separate excitto control the outputeleetromotive force of said dynamo-electric machinethrough the control of said exciting means; and. means comprising a. thermal element for impressing a false excess voltage upon said regulator when a predetermined current overload is I imposed upon said dynamo-electric machine for-a predetermined protracted period.

5. The combinat on witha dynamo-electric machine provided with exciting means,

of -a.voltage regulator of the vibratory type arranged to control the output electromotive through the control of said excitingmeans',

"means for. .-im'pressing only a predetermined portionof the output electromotive force of said'dynamo-electric machine upon the actu-' ating magnets of said regulator under norinal load conditions, and means for impress a ing, a, greater portion of said output electroforce of said dynamo-electric .machine motive force upon said magnets if the in- I ternal temperature of said dynamoelectric machine exceedsa predetermined value by reason; of an abnormal current flow through [the machine for a predetermined protracted -...period. v k In testimony whereof I have hereunto subscribed my name this 17th day of April,

reassure e. Hansen;

85 ing means, of'a voltage regulator arranged 

